Okay...well I've kinda got a headache now trying to figure out what you meant, and remembering those hideous GCSE biology classes. And while you could be right....could it also be that Kessler is just cut muscle, and Beyer....well

If you look at Beyer's forearm it's larger than Kessler's...so he's been doing a lot of right-hand training

(And a cc for a good point, I didn't look at the body measurements really )